Many organisms move directly toward light for prey hunting or navigation, which is called phototaxis. Mimicking this behavior in robots is crucially important in the energy industry and environmental exploration. However, the phototaxis robots with rigid bodies and sensors still face challenges in adapting to unstructured environments, and the soft phototaxis robots often have high requirements for light sources with limited locomotion performance. Here, we report a 3.5 g soft microrobot that can perceive the azimuth angle of light sources and exhibit rapid phototaxis locomotion autonomously enabled by three-dimensional flexible optoelectronics and compliant shape memory alloy (SMA) actuators. The optoelectronics is assembled from a planar patterned flexible circuit with miniature photodetectors, introducing the self-occlusion to light, resulting in high sensing ability (error < 3.5°) compared with the planar counterpart. The actuator produces a straightening motion driven by an SMA wire and is then returned to a curled shape by a prestretched elastomer layer. The actuator exhibits rapid actuation within 0.1 s, a significant degree of deformation (curvature change of ∼87 m-1) and a blocking force of ∼0.4 N, which is 68 times its own weight. Finally, we demonstrated the robot is capable of autonomously crawling toward a moving light source in a hybrid aquatic-terrestrial environment without human intervention. We envision that our microrobot could be widely used in autonomous light tracking applications.

中文翻译：

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基于柔性光电的软爬行微型机器人，可在陆地和水生环境中实现自主趋光。


许多生物体直接向光移动以进行猎物或导航，这称为趋光性。在机器人中模仿这种行为对于能源工业和环境探索至关重要。然而，具有刚体和传感器的趋光机器人在适应非结构​​化环境方面仍然面临挑战，而软趋光机器人往往对光源要求较高，但运动性能有限。在这里，我们报告了一种 3.5 g 软体微型机器人，它可以感知光源的方位角，并通过三维柔性光电器件和顺应形状记忆合金 (SMA) 执行器自主实现快速趋光运动。该光电器件由平面图案化柔性电路和微型光电探测器组装而成，引入了对光的自遮挡，与平面对应器件相比，具有较高的传感能力（误差< 3.5°）。执行器产生由 SMA 线驱动的拉直运动，然后通过预拉伸的弹性体层恢复到卷曲形状。该执行器表现出0.1 s内的快速驱动、显着的变形程度（曲率变化~87 m-1）和~0.4 N的阻挡力，这是其自重的68倍。最后，我们证明了机器人能够在水陆混合环境中自主爬向移动光源，无需人工干预。我们设想我们的微型机器人可以广泛用于自主光跟踪应用。